Embodiments of the invention relate generally to electric vehicle charging and, more particularly, to a system and method for authorizing charging of an electric vehicle via an off-line electric charging station.
Electrically powered vehicles, including electric vehicles and plug-in hybrid electric vehicles, provide a zero- or low-emissions solution for transportation in cities and, in the future, are expected to gradually replace the internal combustion engine vehicle as the primary mode of transportation. Electrically powered vehicles include electric motors powered from energy storage devices, such as batteries. As the vehicles operate, the energy storage devices contained therein are depleted. The energy storage devices are commonly recharged at vehicle charging stations to enable further use of the vehicle. Such vehicle charging stations are designed to charge the energy storage device when connected to the vehicle.
In most charging stations, an access control feature is included that regulates a charging operation between the charging station and the vehicle. That is, the access control feature functions to receive information from a potential user (including payment information), authenticate the user, process the payment information, and/or approve or authorize the power delivery to the vehicle. One example of such an access control feature included in early versions of charging stations was an RFID reader incorporated into the charging station. The RFID reader would interact with an RFID card presented by the user in order to receive information from the user. Information on the RFID card could be stored in a memory/local database of the charging station and/or stored on a remote server, with the local/remote database being accessed (such as via the Internet, a LAN, a WAN, cellular, or other network/data connection for the remote database) to transmit/receive user information, authenticate the user, process payment information, and authorize power delivery to the vehicle.
More recently, the access control feature included in charging stations has been in the form of a platform/system that utilizes smartphone (a.k.a. “mobile app”) authorization and authentication. To enable such smartphone authorization, the charging station is coupled to at least one server through a network, such as the Internet, a LAN, a WAN, cellular, or other network/data connection, with the server communicating with the charging station to receive user information, authenticate the user, process payment information, and authorize power delivery to the vehicle. While this smartphone authorization access control feature is recognized as a convenient and efficient means for regulating a charging operation between the charging station and the vehicle, it is recognized that such smartphone authorization is enabled only when the charging station is in communication with the server. When the charging station is off-line—with it being known that temporary network outages do occasionally occur—the charging request cannot be authorized, thereby potentially leaving the user stranded and unable to get home if their electric vehicle does not have sufficient charge.
Therefore, it is desirable to provide a charging station and method of interacting therewith that enables smartphone authorization of a charging request even when the charging station is off-line from a remote server. It is further desirable that such an authorization method be secure and resistant to tampering, so as to prevent the unregulated charging of an electric vehicle.